Abstract: A roof assembly includes louvers arranged parallel and side by side. Each of the louvers is pivotally coupled to a support structure for rotation about a corresponding pivot axis that is parallel to a length dimension of the louver; At least one actuator is coupled to move the louvers from a closed configuration of the roof assembly wherein each of the plurality of louvers overlaps with each of the other ones of the louvers to which the louver is adjacent and to an open configuration assembly by pivoting each of the louvers about the corresponding pivot axis. The pivot axis is spaced apart from the louver in a dimension transverse to the louver by a first offset distance and spaced below and away from a lower surface of the louver by a second offset distance. Also described are louver actuation mechanisms and couplers useful for coupling louvers to actuation mechanisms.